For convenient lighting control, lighting systems of relatively modern design allow control commands for controlling luminaires to be transmitted to the luminaires or to the operating devices thereof. By way of example, such operating devices for luminaires may be designed to receive control commands produced on the basis of the DALI (“Digital Addressable Lighting Interface”) standard and to implement them for the control of the relevant luminaire. Such systems also allow complex control processes for a lighting system having a plurality of luminaires to be performed under the control of a controller. By way of example, the intensity and/or color and/or color temperature of one or more luminaires can be controlled.
In principle, control can be affected in two different ways. In the case of “absolute” activation or “absolute” actuation, an absolute actuation value that a luminaire is intended to adopt at the end of the process is already certain when the process is initiated and a control command is output to the luminaire. An exemplary scenario is the selection of one of a plurality of prescribed moods of a lighting system, wherein the intensity and color temperature associated with a luminaire are stipulated and a corresponding control command can be generated as soon as the relevant mood is selected. For the absolute activation, the luminaire can be provided with the absolute actuation value as a target. The output of light from the luminaire can be set in accordance with the absolute actuation value, for example in a changeover process.
In the case of “relative” activation or “relative” actuation, the absolute actuation value that the luminaire is meant to adopt at the end of the process is not yet certain at the beginning of the process. Rather, a current actuation value of a manipulated variable of the luminaire needs to be increased or decreased by one or more increments so long as a pushbutton switch is pushed, for example. An exemplary scenario is the adjustment of the intensity during dimming, which can take place in response to the operation of a pushbutton switch for example. In the case of “relative” activation or “relative” actuation, a final value is not yet certain at the beginning of the process. Even the duration of the process is unknown when the process begins. A conventional implementation for the control of luminaires in the case of “relative” activation or “relative” actuation involves the same control command being repeated continually for as long as the process lasts. In this way, by repeatedly outputting the same “UP” or “DOWN” command on the basis of the DALI standard for example, it is possible to achieve an incremental increase or decrease in an actuation value of a luminaire. This approach can result in a relatively high utilization level for a bus system, however. This can make it difficult to execute other commands in a reasonable time.
WO 99/60804 A1 describes information systems in which light control can take place via a network. The operation of a switch allows a light intensity to be increased or decreased, with an appropriate command being produced in each case in response to single operation of a switch. In the event of multiple operation of the switch, a plurality of commands are accordingly produced. A dimming rate can be programmed variably via the network.
DE 10 2006 001 256 A1 describes a method for operating a light source and a lamp operating device in which the lamp operating device receives brightness commands and ascertains a dimming period automatically.